Method for transmitting uplink response signals, base station, mobile station and communication system

ABSTRACT

A method for transmitting uplink response signals, base station, mobile station and communication system, includes judging whether to use a downlink secondary component carrier to transmit data to a mobile station; if the judging result is positive, allocating resources according to the number of transmission blocks for transmitting the downlink data in the secondary component carrier, accordingly the mobile station is able to use the resources corresponding to a preconfigured primary component carrier and the resources allocated to the secondary component carrier to select uplink resources for transmitting response signals.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation or U.S. application Ser. No.13/847,639, filed Mar. 20, 2013, now pending, which is a continuation ofPCT Application No. PCT/CN2010/077150, filed on Sep. 20, 2010, thecontents of each are herein wholly incorporated by reference.

TECHNICAL FIELD

The present invention relates to the field of wireless communication,and in particular to a method for transmitting uplink response signals,base station, mobile station and communication system.

BACKGROUND ART

In a long-term evolution (LTE) system, a user equipment (UE) receivesdownlink data transmitted by a base station, decodes the downlink dataand obtains a response signal of the downlink data based on the decodingresult, then transmits uplink control information containing theresponse signal in a physical uplink control channel (PUCCH), so thatthe base station can judge whether the data transmission is correct orwrong according to the uplink control information and hence judgewhether data retransmission is needed. Wherein, the uplink controlinformation comprises response signals for downlink data, such asacknowledgement (ACK)/negative acknowledgement (NACK)/discontinuoustransmission (DTX), and channel state information (CSI), etc., whereinthe ACK denotes that the data are correctly received, NACK denotes thatthe data are wrongly received, and DTX denotes that the UE receives nodownlink control data, that is, receives no control signaling forscheduling downlink data transmission.

The response signals transmitted in the PUCCH correspond respectively toa physical channel resource, a time domain sequence and a frequencydomain sequence, these three resources being associated with twoparameters. One parameter is parameter N1 configured by a high layer ofthe system and is the same for all the UEs in all cells, and the otherparameter is associated with an index of a first control channel element(CCE) contained in a physical downlink control channel (PDCCH) used forscheduling the downlink data to which the response signals correspond.In particular, N1 determines a starting position of the PUCCH used fortransmitting the response signals, in the frequency domain in an uplinksubframe, and this parameter is shared by all the UE or mobile stationsin the cells; and the index of the first CCE of the PDCCH, together withthe starting position, determine the physical resources and sequenceresources actually used by the UE scheduled in the PDCCH in transmittinguplink control signaling, as shown in FIG. 1.

FIG. 2 is a schematic diagram of the timing sequence of response signaltransmission of an LTE FDD (frequency division duplexing) system. For anLTE FDD system, uplink subframes correspond to downlink subframes one byone. Namely, for any one of the UE in the system, in an uplink subframe,only a response signal value of the data in a downlink subframecorresponding to the uplink subframe is transmitted. The datatransmitted in a downlink subframe contains at most two transmissionblocks (TBs), that means, there exist response signals with two bits.The response signals with two bits need to be modulated into QPSK(quadrature phase shift keying) symbols before transmission, and thenare mapped into corresponding physical resources and sequence resources.The timing sequence of ACK/NACK transmission of an LTE FDD system is asshown in FIG. 2.

FIG. 3 is a schematic diagram of the timing sequence of response signaltransmission of an LTE TDD (time division duplexing) system. In LTE TDDsystem, 7 types of uplink and downlink subframe configuration aredefined. In most of the subframe configuration, one uplink subframecorresponds to multiple downlink subframes in many cases; that is, forany one of the UE in the system, in an uplink subframe, response signalvalues of the data in multiple downlink subframes corresponding to theuplink subframe need to be transmitted. The timing sequence oftransmission of ACK/NACK to which certain uplink and downlink subframeconfiguration corresponds of an LTE TDD system is as shown in FIG. 3.

Currently, a method called channel selection is used in an LTE TDDsystem to transmit response signals, to which the data in multipledownlink subframe correspond, in an uplink subframe. The methodcomprises: if two TBs are contained in the downlink subframe, bundlingthe response signals of the two TBs; for example, when all the responsesignals are ACK, the result is still ACK after bundling, otherwise, theresult is NACK; and then determining modulated symbol values andcorresponding physical resources and sequence resources by looking up atable based on the bundled response signals.

Table 1 shows a response signal feedback method when two downlinksubframes correspond to one uplink subframe. As shown in Table 1, if theresponse signals detected by the UE in the two subframes are (ACK, ACK),the lowest CCE index n1 of the PDCCH used for scheduling the UE toperform downlink signal transmission, in the first subframe is chosenfor uplink physical resources and sequence resources mapping, with avalue of modulation symbol being −1, and if the response signals towhich the two subframes correspond are (ACK, NACK/DTX), the lowest CCEindex n0 of the PDCCH in the 0th subframe is chosen for uplink physicalresources and sequence resources mapping, with a value of modulationsymbol being j, and other channel selection schemes may be deducted byanalogy according to Table 1. In general, the number of resources neededin channel selection is equal to the number of bits of the responsesignals; for example, if the numbers of the response signals are 2, 3 or4 bits, 2, 3 or 4 resources are needed respectively.

TABLE 1 A channel selection scheme for response signals with 2 bits inan LTE system Response signal 1, Response signal 2 Resources b(0), b(1)ACK, ACK n1 −1 ACK, NACK/DTX n0 −j NACK/DTX, ACK n1  1 NACK/DTX, NACK n1j NACK, DTX n0 j DTX, DTX N/A N/A

It can be seen from above that in an LTE TDD system, as bundling ofresponse signals is used, an available resource may be obtained fromeach downlink subframe containing data transmission. Hence, theresources are sufficient when the response signals values fed back aremapped to the resources.

In an LTE-advanced (LTE-A) system, carrier aggregation (CA) is used indata transmission, in which the uplink and downlink containing multiplecomponent carriers (CC), and uplink data transmission and downlink datatransmission may be scheduled in each component carrier for a mobilestation in the system. The system configures each UE with a downlinkprimary component carrier (PCC) and multiple secondary componentcarriers (SCCs). The data transmitted in the PCC and SCCs is scheduledrespectively.

In the LTE-A system, for any UE, control information, such as responsesignals of the data of each downlink component carrier and channel stateinformation (CSI) of the downlink component carrier, etc., to which allthe configured downlink SCCs of the UE correspond, is fed back in theuplink PCC of the UE. This is similar to the LTE TDD, that is, themobile station needs to feed back response signals values of the data inmultiple downlink subframes in an uplink subframe of one PCC, thedownlink subframes belonging to different downlink component carriers(CCs).

However, in the implementation of the present invention, the inventorfound following defects existing in the prior art of an LTE-A system,when carrier aggregation scheme is adopted, as resources to which a PCCcorresponds are pre-configured, when a base station transmits data byusing SCCs, a case of insufficient resources exists because bundling isnot adopted in accordance with the requirement of a single carrier.

For example, when a mobile station is configured with 2 CCs, that is, aPCC and a PCC, and 2 TBs are transmitted in each of the CCs, 4 responsesignals values are needed to be fed back and 4 resources are needed forselection; while in a general case, resources to which a PCC correspondsare normally pre-configured, in this case, if mapping is performed byusing only the lowest CCE index of the PDCCH in each CC, the number ofthe available resources is only 2.

There is no effective solution for the case of resources insufficienttill now.

Following documents are listed for the easy understanding of the presentinvention and conventional technologies, which are incorporated hereinby reference as they are fully stated in this text.

1) CN101594211A, published in Dec. 2, 2009, and entitled Method forsending correct/wrong response message in multicarrier system with bigbandwidth;

2) CN101588226A, published in Nov. 25, 2009, and entitled Terminal inlarge bandwidth multi-carrier system and a sending method of responsemessage; and

3) WO2010/050688A2, entitled Method of HARQ acknowledgement transmissionand transport block retransmission in a wireless communication system.

SUMMARY OF THE INVENTION

An object of the embodiment of the present invention is to provide amethod for transmitting uplink response signals, base station, mobilestation and communication system, wherein, the base station allocatesextra resource, such that UE feeds back response signals by usingpreconfigured resources and the extra allocated resources, feeding backthe response signals at a relatively low cost, and solving the problemof insufficient resources in the prior art.

According to an aspect of the embodiments of the present invention,there is provided a method for transmitting uplink response signals,comprising:

judging whether to use a downlink secondary component carrier totransmit data to a mobile station;

if the judging result is positive, allocating resources according to thenumber of transmission blocks for transmitting the downlink data in thesecondary component carrier, such that the mobile station is able to usethe resources corresponding to a preconfigured primary component carrierand the resources allocated to the secondary component carrier to selectuplink resources for transmitting response signals.

According to another aspect of the embodiments of the present invention,there is provided a method for transmitting uplink response signals,comprising:

receiving the downlink data transmitted by a base station via a downlinkcomponent carrier;

decoding the received downlink data, and obtaining response signals ofthe downlink data according to the decoding result;

selecting uplink resources for transmitting the response signals fromavailable resources and selecting corresponding modulation symbols ifthe component carrier for transmitting the downlink data includes asecondary component carrier; wherein the available resources includeresources corresponding to a preconfigured primary component carrier andthe resources allocated to the secondary component carrier by the basestation; and

transmitting the response signals by using the selected uplink resourcesand the corresponding modulation symbols.

According to still another aspect of the embodiments of the presentinvention, there is provided a base station, comprising:

a judging unit configured to judge whether a downlink secondarycomponent carrier is used to transmit data to a mobile station;

a resource allocating unit configured to allocate resources according tothe number of the transmission blocks for transmitting downlink data viathe secondary component carrier if the judging result of the judgingunit is positive, such that the mobile station is able to use theresources corresponding to a preconfigured primary component carrier andthe resources allocated to the secondary component carrier to select theuplink resources for transmitting response signals.

According to a further aspect of the embodiments of the presentinvention, there is provided a mobile station, comprising:

a data receiving unit configured to receive the downlink datatransmitted by a base station via a downlink component carrier;

a data processing unit configured to decode the received downlink data,and obtain the response signals of the downlink data according to thedecoding result;

a first resource selecting unit configured to select the uplinkresources for transmitting the response signals from available resourcesand select corresponding modulation symbols, if the component carrierfor transmitting the downlink data includes a secondary componentcarrier; wherein the available resources include resources correspondingto a preconfigured primary component carrier and the resources allocatedto the secondary component carrier by the base station; and

a signal transmitting unit configured to transmit the response signalsby using the selected uplink resources and the corresponding modulationsymbols.

According to a further still aspect of the embodiments of the presentinvention, there is provided a communication system, comprising:

a base station, comprising the above-described base station; and

a mobile station, comprising the above-described mobile station.

According to a further still aspect of the embodiments of the presentinvention, there is provided a computer-readable program, wherein whenthe program is executed in a base station, the program enables acomputer to carry out the above-described method for transmitting uplinkresponse signals in the base station.

According to a further still aspect of the embodiments of the presentinvention, there is provided a storage medium storing acomputer-readable program, wherein the computer-readable program enablesa computer to carry out the above-described method for transmittinguplink response signals in a base station.

According to a further still aspect of the embodiments of the presentinvention, there is provided a computer-readable program, wherein whenthe program is executed in a mobile station, the program makes acomputer to carry out the above-described method for transmitting uplinkresponse signals in the mobile station.

According to a further still aspect of the embodiments of the presentinvention, there is provided a storage medium storing acomputer-readable program, wherein the computer-readable program enablesa computer to carry out the above-described method for transmittinguplink response signals in a mobile station.

The advantages of the present invention exist in that, by allocatingextra resource by the base station, the UE may feed back responsesignals by using preconfigured resources and the extra allocatedresources, and may feed back the response signals at a relatively lowcost which solves the problem of insufficient resources in the priorart.

These and further aspects and features of the present invention will beapparent with reference to the following description and attacheddrawings. In the description and drawings, particular embodiments of theinvention have been disclosed in detail as being indicative of some ofthe ways in which the principles of the invention may be employed, butit is understood that the invention is not limited correspondingly inscope. Rather, the invention includes all changes, modifications andequivalents coming within the spirit and terms of the appended claims.

Features that are described and/or illustrated with respect to oneembodiment may be used in the same way or in a similar way in one ormore other embodiments and/or in combination with or instead of thefeatures of the other embodiments.

It should be emphasized that the term “comprises/comprising” when usedin this specification is taken to specify the presence of statedfeatures, integers, steps or components but does not preclude thepresence or addition of one or more other features, integers, steps,components or groups thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of the mapping of the uplink and downlinkcontrol channels of an LTE system;

FIG. 2 is a schematic diagram of the timing sequence of response signaltransmission of an LTE FDD system;

FIG. 3 is a schematic diagram of the timing sequence of response signaltransmission of an LTE TDD system;

FIG. 4 is a flowchart of the method for transmitting uplink responsesignals in accordance with the 1st embodiment of the present invention;

FIG. 5 is a flowchart of the method for transmitting uplink responsesignals in accordance with the 2nd embodiment of the present invention;

FIG. 6 is a flowchart of the method for transmitting uplink responsesignals in accordance with the 3rd embodiment of the present invention;

FIG. 7 is a schematic diagram of the structure of the base station inaccordance with the 4th embodiment of the present invention;

FIG. 8 is a schematic diagram of the structure of the resourceallocating unit in FIG. 7;

FIG. 9 is a schematic diagram of the structure of the mobile station inaccordance with the 5th embodiment of the present invention; and

FIG. 10 is a schematic diagram of the structure of the communicationsystem in accordance with the 6th embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments of the present invention are described as follows withreference to the drawings. These embodiments are illustrative only, andare intended to limit the present invention. For easy understanding ofthe principle and embodiments of the present invention by those skilledin the art, the embodiments of the present invention shall be describedtaking an LTE-A system of 3GPP using CA scheme for transmitting data asan example. However, it should be understood the present invention isnot limited to the LTE-A system, and is also applicable similarmulticarrier communication systems having a CA function.

FIG. 4 is a flowchart of the method for transmitting uplink responsesignals of the first embodiment of the present invention. As shown inFIG. 4, the method comprises:

Step 401: judging whether to use a downlink SCC to transmit data to amobile station when a base station transmits data to the mobile station;and if the judging result is positive, performing step 402; otherwise,performing step 403;

Step 402: if the judging result in step 401 is positive, allocatingresources according to the number of transmission blocks fortransmitting the downlink data in the secondary component carrier, suchthat the mobile station is able to use the resources corresponding to apreconfigured primary component carrier and the resources allocated tothe secondary component carrier to select uplink resources fortransmitting response signals.

In this embodiment, in step 401, if the base station determines to usethe downlink SCC to transmit data, a case of insufficient of resourcesoccurs; in this case, the base station may allocate resources for theSCC, such that the mobile station feeds back the response signals byusing preconfigured resources and extra allocated resources.

In this embodiment, the method further comprise step 403: if the judgingresult in step 401 is negative, it shows that a PCC is used to transmitdownlink data; as resources to which the PCC corresponds arepre-configured, no extra resource is needed to be allocated, and themobile station may use the preconfigured resources to feed back theresponse signals.

It can be seen from the above embodiment that in the case ofinsufficient resources, the base station allocates extra resource, sothat the mobile station may obtain the allocated resources and feed backresponse signals by using the preconfigured resources and the extraallocated resources, and may feed back the response signals at arelatively low cost without breaking the uplink single carrierproperties which solves the problem of insufficient resources in theprior art.

FIG. 5 is a flowchart of the method for transmitting uplink responsesignals in accordance with the second embodiment of the presentinvention. As shown in FIG. 5, the method comprises:

step 501: judging whether to use a downlink SCC to transmit data to amobile station when a base station transmits data to the mobile station;and if the judging result is positive, performing step 502; otherwise,performing step 505;

wherein, the base station may determine whether to apply downlink SCC totransmit data to the mobile station in accordance with the channelquality signal transmitted from the mobile station, which may be carriedout by using any existing manner, and shall not be described anyfurther.

step 502: if the judging result in step 401 is positive, allocatingresources according to the number of TBs for transmitting the downlinkdata in the SCC, such that the mobile station is able to use theresources corresponding to a preconfigured PCC and the resourcesallocated to the SCC to select uplink resources for transmittingresponse signals;

wherein the following methods may be used to allocate the resources:

method 1: if the number of TBs for transmitting the downlink data is 1,selecting resources from a preconfigured first resource table, each ofthe elements in the first resource table comprising 1 resource; wherein,following cases are included: the number of the configured TBs is 1; andthe number of the configured TBs is 2 but the number of the TBs actuallyused in data transmission is 1; for example, the first resource set 1 isas shown in Table 1:

TABLE 1 r1 r2 r 3 r 4 r5 r6 r 7 r 8

method 2: if the number of TBs for transmitting the downlink data is 2,selecting resources from a preconfigured second resource table, each ofthe elements in the second resource table comprising 2 resources, forexample, the second resource set 2 is as shown in Table 2:

TABLE 2 (r1, (r3, (r5, (r7, (r8, (r11, (r13, (r15, r2) r4) r6) r8) r10)r12) r14) r16)

step 503: transmitting the indices of the allocated resources to themobile station;

wherein the indices of the resources may be transmitted to the mobilestation via a PDCCH in the SCC scheduling the downlink data;

step 504: transmitting downlink data by the base station to the mobilestation by using the PCC and the SCC, such that the mobile stationdecodes the downlink data after receiving the downlink data to obtaincorresponding response signals, and feeds back the response signals byusing the preconfigured resources and the extra allocated resources; and

step 505: if the judging result in step 501 is negative, as resources towhich the PCC corresponds are pre-configured, no extra resource isneeded to be allocated, the PCC is used to transmit downlink data, andthe mobile station may use the preconfigured resources to feed back theresponse signals.

It can be seen from the above embodiment that in the case ofinsufficient resources, the base station allocates extra resource basedon the number of TBs used for transmitting data, and transmits theindices of the resources to the mobile station via a PDCCH in the SCCscheduling the downlink data, so that the mobile station may obtain theallocated resources and feed back response signals by using thepreconfigured resources and the extra allocated resources, and may feedback the response signals at a relatively low cost without breaking theuplink single carrier properties which solves the problem ofinsufficient resources in the prior art.

FIG. 6 is a flowchart of the method for transmitting uplink responsesignals in accordance with the third embodiment of the presentinvention. As shown in FIG. 6, the method comprises:

Step 601: receiving the downlink data transmitted by a base station viaa downlink CC;

Step 602: decoding the received downlink data, and obtaining responsesignals of the downlink data according to the decoding result;

Step 603: selecting uplink resources for transmitting the responsesignals from available resources and selecting corresponding modulationsymbols if the CC for transmitting the downlink data includes a SCC;wherein the available resources include resources corresponding to apreconfigured PCC and the resources allocated to the SCC by the basestation; and

Step 604: transmitting the response signals by using the selected uplinkresources and the corresponding modulation symbols.

It can be seen from the above embodiment that in the case ofinsufficient resources, the base station allocates extra resource basedon the number of TBs used for transmitting data, and transmits theindices of the resources to the mobile station via a PDCCH, the mobilestation may feed back response signals by using the preconfiguredresources and the extra allocated resources, and may feed back theresponse signals at a relatively low cost without breaking the uplinksingle carrier properties which solves the problem of insufficientresources in the prior art.

In this embodiment, in step 602, there are three types of responsesignals, namely, ACK, NACK and DTX; wherein ACK (hereinafter expressedas A) denotes that the data are correctly received, NACK (hereinafterexpressed as N) denotes that the data are wrongly received, and DTX(hereinafter expressed as D) denotes no downlink control data isreceived, that is, no control signaling for scheduling downlink datatransmission is received.

In this embodiment, in step 603, as the base station uses the SCC totransmit downlink data, insufficient of resources occurs; as such, thebase station allocates extra resources for the SCC, such that the mobilestation selects uplink resources for transmitting response signals fromthe preconfigured resources and the allocated resources; wherein theextra allocated resources are PUCCH resources.

In this embodiment, in step 604, the mobile station uses the selecteduplink resources and the corresponding modulation symbols to transmitthe response signals; wherein a QPSK modulation may be used to transmitthe response signals in the selected resources.

In this embodiment, different response states are mapped by using theuplink resources and the modulation symbols in the uplink resources. Inthis way, the mobile station may select the uplinks resources and selectcorresponding modulation symbols according to the response states. Thus,the mobile station may transmit the modulation symbols, and the basestation may judge whether the transmitted downlink data are correctlyreceived after receiving the modulation symbols. This is similar to theprior art, which shall not be described any further.

In this embodiment, if the base station allocates extra resources to theSCC, the base station transmits the indices of the allocated resourcesto the mobile station. Therefore, the method further comprises:receiving, by the mobile station, indices of the resources allocated bythe base station for the SCC and transmitted by the base station.

In this embodiment, the method further comprises step 605: selectinguplink resources for transmitting the response signals from theavailable resources and selecting corresponding modulation symbols ifthe CC for transmitting the downlink data is a PCC; wherein theavailable resources include resources corresponding to the preconfiguredprimary component carrier.

In this embodiment, in steps 603 and 605, the manner below may be usedin selecting the uplink resources for transmitting the response signalsby using the available resources:

selecting the uplink resources for transmitting the response signals andthe modulation symbols by using a preconfigured mapping relation betweenthe state of the response signals and the selected resources and themodulation symbols according to the state of the response signals;wherein a selected resource is one of the available resources;

wherein in the mapping relation, the resource corresponding to theresponse signal that is N/D is not selected; N and D are notdifferentiated, where N represents data is received with error, and Drepresents no downlink control data is received; and when the responsesignals are all N/D, no resource is selected.

and wherein a preconfigured mapping relations table may be looked upaccording a number of bits of the response signals, the number of theresources available for selection (the number of the availableresources) in the mapping relations table being equal to the number ofthe bits of the response signals. Following description is given takingthat the numbers of the response signals are 4 bits, 3 bits and 2 bitsas examples.

First, the number of the response signals is 4 bits

Following cases are included when the number of the response signals is4 bits:

1) 2 CCs are configured for the mobile station, the transmission modeconfigured for each of the CCs containing 2 TBs;

2) 3 CCs are configured for the mobile station, the transmission modeconfigured for one of the CCs containing 2 TBs, and the transmissionmode configured in each of the other two CCs containing 1 TB; and

3) 4 CCs are configured for the mobile station, the transmission modeconfigured for each of the CCs containing 1 TB.

In these cases, the number of the resources available for selection,i.e. the number of the available resources, is 4; the relation betweenthe state of the response signals of the mobile station and theavailable resources is as shown in Table 3A, in which the resourcesavailable for selection are one or more of the available resources; andfor response signals with 4 bits, the mapping relation between the stateof the response signals and the selected resources and the modulationsymbols is as shown in Table 3B, in which the resources available forselection are one of the available resources (selectable resources).

TABLE 3A Available resources for response signals with 4 bits AvailableNo. R0 R1 R2 R3 Resources 1 A A A A n0, n1, n2, n3 2 A A A N/D n0, n1,n2 3 A A N/D A n0, n1, n3 4 A A N/D N/D n0, n1 5 A N/D A A n0, n2, n3 6A N/D A N/D n0, n2 7 A N/D N/D A n0, n3 8 A N/D N/D N/D n0 9 N/D A A An1, n2, n3 10 N/D A A N/D n1, n2 11 N/D A N/D A n1, n3 12 N/D A N/D N/Dn1 13 N/D N/D A A n2, n3 14 N/D N/D A N/D n2 15 N/D N/D N/D A n3 16 NN/D N/D N/D n0 17 D N/D N/D N/D N/A

TABLE 3B Mapping relation of response signals with 4 bits SelectedModulation No. R0 R1 R2 R3 Resources symbols 1 A A A A n3 −1 2 A A A N/Dn1 −1 3 A A N/D A n3  j 4 A A N/D N/D n0  j 5 A N/D A A n2 −1 6 A N/D AN/D n2  j 7 A N/D N/D A n3 −j 8 A N/D N/D N/D n0 −1 9 N/D A A A n1 −j 10N/D A A N/D n1  1 11 N/D A N/D A n1 −j 12 N/D A N/D N/D n0 −j 13 N/D N/DA A n2 −j 14 N/D N/D A N/D n2  1 15 N/D N/D N/D A n3  1 16 N N/D N/D N/Dn0  1 17 D N/D N/D N/D N/A N/A

where, in the mapping relations shown in tables 3A and 3B, numbers 1-17denote 17 states to which the response signals correspond, A denotesthat the data are correctly received, N denotes that the data arereceived with error, D denotes that no downlink control data isreceived, n0-n3 denote the available resources, that is, resourcesavailable for selection and N/A denotes being unapplicable; whereinA=ACK, N=NACK, and D=DTX. NACK and DTX are not differentiated in tables3A and 3B. Taken state 4 (A,A,N/D,N/D) as an example, the responsesignals that are contained may be:

(A,A,N,N), (A,A,N,D), (A,A,D,N), (A,A,D,D).

It can be seen from above that in each of the states available forselection except for states 16 and 17, the serial numbers of theresponse signals to which A corresponds are consistent with the serialnumbers of the resources to which the A corresponds. For example, forstate 10, the serial numbers of the response signals to which Acorresponds are 1 and 2, correspondingly, the serial numbers ofavailable resources are also 1 and 2.

Furthermore, for state 16, as only the first response signal is a fixedN, the first resource can only be selected as the selected resource.States 16 and 17 may be combined into a state (N/D,N/D,N/D,N/D), inwhich no resource is selected for mapping it.

Second, the number of the response signals is 3 bits.

Following cases are included when the number of the response signals is3 bits:

1) 2 CCs are configured for the mobile station, the transmission modeconfigured in one of the CCs containing 2 TBs, and the transmission modeconfigured in the other CC containing 1 TB; and

2) 3 CCs are configured for the mobile station, the transmission modeconfigured in each of the CCs containing 1 TB.

In these cases, the number of the resources available for selection,i.e. the number of the available resources, is 3; the relation betweenthe state of the response signals of the mobile station and theavailable resources is as shown in Table 4A, in which the resourcesavailable for selection are one or more of the available resources; andfor response signals with 3 bits, the mapping relation between the stateof the response signals and the selected resources and the modulationsymbols is as shown in Table 4B, in which the resources available forselection are one of the available resources (selectable resources).

TABLE 4A Available resources for response signals with 3 bits AvailableNo. R0 R1 R2 resources 1 A A A n0, n1, n2 2 A A N/D n0, n1 3 A N/D A n0,n2 4 A N/D N/D n0 5 N/D A A n1, n2 6 N/D A N/D n1 7 N/D N/D A n2 8 N N/DN/D n0 9 D N/D N/D N/A

TABLE 4B Mapping relation of response signals with 3 bits SelectedModulation No. R0 R1 R2 Resources symbols 1 A A A n2 −1  2 A A N/D n1 −j3 A N/D A n0 j 4 A N/D N/D n0 −1  5 N/D A A n1 1 6 N/D A N/D n1 j 7 N/DN/D A n2 1 8 N N/D N/D n0 1 9 D N/D N/D N/A N/A

where, in the mapping relations shown in tables 4A and 4B, numbers 1-9denote the states to which the response signals correspond, A denotesthat the data are correctly received, N denotes that the data arereceived with error, D denotes that no downlink control data isreceived, n0-n2 denote the available resources, that is, resourcesavailable for selection and N/A denotes being unapplicable.

Third, the number of the response signals is 2 bits

Two CCs are configured for the mobile station, the transmission modeconfigured in each of the CCs containing 1 TB.

In this case, the number of the resources available for selection, i.e.the number of the available resources, is 2; the relation between thestate of the response signals of the mobile station and the availableresources is as shown in Table 5A, in which the resources available forselection are one or more of the available resources; and for 2 bits ofresponse signals, the mapping relation between the state of the responsesignals and the selected resources and the modulation symbols is asshown in Table 5B, in which the resources available for selection areone of the available resources (selectable resources).

TABLE 5A Available resources for response signals with 2 bits AvailableNo. R0 R1 resources 1 A A n0, n1 2 A N/D n0 3 N/D A n1 4 N N/D n0 5 DN/D N/A

TABLE 5B Mapping relation of response signals with 2 bits AvailableModulation No. R0 R1 Resources symbols 1 A A n1 −j 2 A N/D n0 −1 3 N/D An1 j 4 N N/D n0  1 7 D N/D N/A N/A

where, in the mapping relations shown in tables 5A and 5B, numbers 1-5denote the states to which the response signals correspond, A denotesthat the data are correctly received, N denotes that the data arereceived with error, D denotes that no downlink control data isreceived, n0-n2 denote the available resources, i.e. resources availablefor selection, and N/A denotes being unapplicable.

Furthermore, in this embodiment, in steps 603 and 605, the manner belowmay be used in selecting the uplink resources for transmitting theresponse signals by using the available resources:

selecting the uplink resources for transmitting the response signals andthe modulation symbols by using a preconfigured mapping relation betweenthe state of the response signals and the selected resources and themodulation symbols according to the state of the response signals;wherein a selected resource is one of the available resources;

wherein in the mapping relation, the resource corresponding to theresponse signal that is N/D is not selected; N and D are notdifferentiated, where N represents data is received with error, and Drepresents no downlink control data is received; and when the responsesignals are all N/D, no resource is selected.

In addition, no matter how many CCs are configured for the mobilestation, if the downlink data are only transmitted in the PCC, themapping needs to be performed by using resource mapping scheme in LTE,i.e. the lowest CCE index of the PDCCH in the PCC.

Following description is give for mapping relations of response signalswith 4 bits and configured with 2CCs, 3CCs and 4 CCs and for mappingrelations of response signals with 3 bits and configured with 2CCs and3CCs.

First, response signals with 4 bits

When the response signals are 4 bits, and the mobile station isconfigured with 2 CCs, with the transmission mode configured in each ofthe CCs containing 2 TBs, the resources available for selection by themobile station is as shown in Table 6A, and the mapping relation is asshown in Table 6B.

TABLE 6A Resources available for selection by response signals with 4bits and configured with 2 CCs Available No. CC1, R0 CC1, R1 CC2, R2CC2, R3 resources 1 A A A A n1, n2, n3 2 A A A N n1, n2 3 A A N A n1,n2, n3 4 A A N/D N/D n0 5 A N A A n2, n3 6 A N A N n2 7 A N N A n2, n3 8A N N/D N/D n0 9 N A A A n1, n2, n3 10 N A A N n1, n2 11 N A N A n1, n2,n3 12 N A N/D N/D n0 13 N/D N/D A A n2, n3 14 N/D N/D A N n2 15 N/D N/DN A n2, n3 16 N N N/D N/D n0 17 D D N/D N/D N/A

In the mapping relation shown in Table 6A, the resource corresponding tothe response signal that is N/D is not selected, and when a secondresponse signal belonging to the same CC is N, the resourcecorresponding to the response signal that is N is not selected. This isfor the consideration of the following: if the CC is configured with 2TBs, only one of the TBs is used for transmission actually, and thesecond response signal is fixedly set to be NACK, that is, this NACK hasno corresponding resource.

In addition, if the CC1 in Table 6A is a PCC, for following the aboveprinciple, the first CCE index of the PDCCH of the PCC, i.e. n0, must beselected in columns 4, 8, 12 and 16 in Table 6A, to perform resourcemapping, and n0 is no longer used as a selected resource for the statesof other response signals.

TABLE 6B Mapping relation of response signals with 4 bits and configuredwith 2 CCs CC1, CC1, CC2, CC2, Available Modulation No. R0 R1 R2 R3resources symbols 1 A A A A n3 −1 2 A A A N n1 −1 3 A A N A n3  j 4 A AN/D N/D n0 −1 5 A N A A n3  1 6 A N A N n2  1 7 A N N A n1  1 8 A N N/DN/D n0  j 9 N A A A n3 −j 10 N A A N n1  j 11 N A N A n1 −j 12 N A N/DN/D n0 −j 13 N/D N/D A A n2 −1 14 N/D N/D A N n2  j 15 N/D N/D N A n2 −j16 N N N/D N/D n0  1 17 D D N/D N/D N/A N/A

where, in the mapping relations shown in tables 6A and 6B, numbers 1-17denote the states to which the response signals correspond, A denotesthat the data are correctly received, N denotes that the data arereceived with error, D denotes that no downlink control data isreceived, n0-n3 denote the available resources, i.e. resources availablefor selection, and N/A denotes being unapplicable.

Second, response signals with 4 bits

When the response signals are 4 bits, and the mobile station isconfigured with 3 CCs, with the transmission mode configured in one ofthe CCs containing 2 TBs and the transmission mode configured in theother two CCs containing 1 TB, the resources available for selection bythe mobile station is as shown in Table 7A, and the mapping relation isas shown in Table 7B.

TABLE 7A Resources available for selection by response signals with 4bits Available No. CC1, R0 CC1, R1 CC2, R2 CC3, R3 resources 1 A A A An1, n2, n3 2 A A A N/D n1 3 A A N/D A n1, n3 4 A A N/D N/D n0 5 A N A An2, n3 6 A N A N/D n2 7 A N N/D A n3 8 A N N/D N/D n0 9 N A A A n1, n2,n3 10 N A A N/D n1 11 N A N/D A n1, n3 12 N A N/D N/D n0 13 N/D N/D A An2, n3 14 N/D N/D A N/D n2 15 N/D N/D N/D A n3 16 N N N/D N/D n0 17 D DN/D N n3 18 D D N/D D N/A

In the mapping relation shown in Table 7A, the resource corresponding tothe response signal that is N/D is not selected, and when a secondresponse signal belonging to the same CC is N, the resourcecorresponding to the response signal that is N is not selected. This isfor the consideration of the following: if the CC is configured with 2TBs, but only one of the TBs is used for transmission actually, and thesecond response signal is set to be NACK, that is, this NACK has nocorresponding resource.

In addition, if the PCC contains 2 TBs, the CC1 in Table 7A is a PCC,for following the above principle, the first CCE index of the PDCCH ofthe PCC, i.e. n0, must be selected in columns 4, 8, 12 and 16 in Table6A, to perform resource mapping, and n0 is no longer used as a selectedresource for the states of other response signals.

And if the PCC contains 1 TB, the CC3 in Table 7A is a PCC, forfollowing the above principle, a state 17, i.e. (D,D,N/D,N), is newlyadded into Table 7A, and the first CCE index of the PDCCH of the PCC fortransmitting this TB, i.e. n3, is used to perform resource mapping forthis newly added state, together with state 15.

TABLE 7B Mapping relation of response signals with 4 bits and configuredwith 3 CCs CC1, CC1, CC2, CC3, Selected Modulation No. R0 R1 R2 R3resources symbols 1 A A A A n3 −1 2 A A A N/D n1 −1 3 A A N/D A n3  j 4A A N/D N/D n0 −1 5 A N/D A A n2 −1 6 A N/D A N/D n2  j 7 A N/D N/D A n3−j 8 A N/D N/D N/D n0  j 9 N/D A A A n1 −j 10 N/D A A N/D n1  1 11 N/D AN/D A n1 −j 12 N A N/D N/D n0 −j 13 N/D N/D A A n2 −j 14 N/D N/D A N/Dn2  1 15 N/D N/D N/D A n3  1 16 N N/D N/D N/D n0  1 17 D D N/D N n1  j18 D D N/D D N/A N/A

where, in the mapping relations shown in tables 7A and 7B, numbers 1-18denote the states to which the response signals correspond, A denotesthat the data are correctly received, N denotes that the data arereceived with error, D denotes that no downlink control data isreceived, n0-n3 denote the available resources, i.e. resources availablefor selection, and N/A denotes being unapplicable.

Third, 3 bits of response signals

When the response signals are 3 bits, and the mobile station isconfigured with 2 CCs, with the transmission mode configured in one ofthe CCs containing 2 TBs and the transmission mode configured in theother CC containing 1 TB, the resources available for selection by themobile station is as shown in Table 8A, and the mapping relation is asshown in Table 8B.

TABLE 8A Resources available for selection by response signals with 3bits and configured with 2 CCs Available No. CC1, R0 CC1, R1 CC2, R2resources 1 A A A n1, n2 2 A A N/D n0 3 A N A n2 4 A N N/D n0 5 N A An1, n2 6 N A N/D n0 7 N/D N/D A n2 8 N N D n0 9 N/D N/D N n2 10 D D DN/A

In the mapping relation shown in Table 8A, the resource corresponding tothe response signal that is N/D is not selected, and when a secondresponse signal belonging to the same CC is N, the resourcecorresponding to the response signal that is N is not selected. This isfor the consideration of the following: if the CC is configured with 2TBs, but only one of the TBs is used for transmission actually, and thesecond response signal is fixedly set to be NACK, that is, this NACK hasno corresponding resource.

In addition, if the PCC contains 2 TBs, the CC1 in Table 8A is a PCC,for following the above principle, the first CCE index of the PDCCH ofthe PCC, i.e. n0, must be selected in columns2, 4, 6 and 8 in Table 8A,to perform resource mapping, and n0 is no longer used as a selectedresource for the states of other response signals.

And if the PCC contains 1 TB, the CC2 in Table 8A is a PCC, forfollowing the above principle, the first CCE index of the PDCCH of thePCC for transmitting this TB, i.e. n3, is used to perform resourcemapping for states 7 and 9 in Table 8A.

TABLE 8B Mapping relation of response signals with 3 bits and configuredwith 2 CCs Available Modulation No. CC1, R0 CC1, R1 CC2, R2 resourcessymbols 1 A A A n1 −1 2 A A N/D n0 −1 3 A N A n2 j 4 A N N/D n0 j 5 N AA n1  1 6 N A N/D n0 −j 7 N/D N/D A n2 −1 8 N N D n0  1 9 N/D N/D N n2 1 10 D D D N/A N/A

where, in the mapping relations shown in tables 8A and 8B, numbers 1-10denote the states to which the response signals correspond, A denotesthat the data are correctly received, N denotes that the data arereceived with error, D denotes that no downlink control data isreceived, n0-n2 denote the available resources, i.e. resources availablefor selection, and N/A denotes being unapplicable.

It can be seen from the above embodiment that in the case ofinsufficient resources, the base station allocates extra resource basedon the number of TBs used for transmitting data, and transmits theindices of the resources to the mobile station via a PDCCH, so that themobile station may feed back response signals by using the preconfiguredresources and the extra allocated resources, and may feed back theresponse signals at a relatively low cost without breaking the uplinksingle carrier properties which solves the problem of insufficientresources in the prior art.

It should be understood by those skilled in the art that all or part ofthe steps in the methods of the above embodiments may be implemented byrelated hardware instructed by a program, and the program may be storedin a computer-readable storage medium. In executing the program, all orpart of the steps in the methods of the above embodiments may beincluded, and the storage medium may comprise an ROM, an RAM, a floppydisk, and a compact disk, etc.

An embodiment of the present invention provides also a base station anda mobile station as described below. As the principles of the basestation and the mobile station for solving problems are similar to thoseof the method for transmitting uplink response signal based on a basestation and a mobile station as described above, the implementation ofthe method may be referred to for the implementation of the base stationand the mobile station, and the repeated parts shall not be describedfurther.

FIG. 7 is a schematic diagram of the structure of the base station inaccordance with the 4th embodiment of the present invention. As shown inFIG. 7, the base station comprises a judging unit 701 and a resourceallocating unit 702; wherein the judging unit 701 is used for judgingwhether a downlink secondary component carrier is used to transmit datato a mobile station; and the resource allocating unit 702 is used forallocating resources according to the number of the transmission blocksfor transmitting downlink data via the secondary component carrier ifthe judging result of the judging unit 701 is positive, such that themobile station is able to use the resources corresponding to apreconfigured primary component carrier and the resources allocated tothe secondary component carrier to select the uplink resources fortransmitting response signals.

As shown in FIG. 7, the base station further comprises an informationtransmitting unit 703 for transmitting indices of the resourcesallocated by the resource allocating unit 702 to the mobile station.Wherein, the indices of the resources may be transmitted to the mobilestation in a PDCCH scheduling data transmission. However, it is notlimited thereto, and other manners may be used for transmission.

It can be seen from the above embodiment that when data are transmittedvia SCCs, a case of insufficient of resources occurs. As such, the basestation allocates extra resource based on the number of TBs used fortransmitting data, and transmits the indices of the resources to themobile station via a PDCCH, so that the mobile station may feed backresponse signals by using the preconfigured resources and the extraallocated resources, and may feed back the response signals at arelatively low cost which solves the problem of insufficient resourcesin the prior art.

FIG. 8 is a schematic diagram of the structure of the resourceallocating unit in FIG. 7. As shown in FIG. 8, the resource allocatingunit 702 comprises a first resource allocating unit 801 and a secondresource allocating unit 802; wherein the first resource allocating unit801 is used for selecting resources from a preconfigured first resourcetable if the number of the transmission blocks for transmitting downlinkdata is 1, each of the elements in the first resource table including 1resource; and second resource allocating unit 802 is used for selectingresources from a preconfigured second resource table if the number ofthe transmission blocks for transmitting downlink data is 2, each of theelements in the second resource table including 2 resources.

Wherein, Table 1 and Table 2 may be referred to for the first resourcetable and the second resource table, which shall not be described anyfurther.

Furthermore, the base station may comprise a storage unit (not shown)for storing the preconfigured Table 1 and Table 2. And the resources ofTable 1 and Table 2 are shared by all the mobile stations. The basestation may further comprise a data transmitting unit (not shown) fortransmitting downlink data to the mobile station via CCs.

FIG. 9 is a schematic diagram of the structure of the mobile station inaccordance with the 5th embodiment of the present invention. As shown inFIG. 9, the mobile station comprises a data receiving unit 901, a dataprocessing unit 902, a first resource selecting unit 909 and a signaltransmitting unit 904; wherein the data receiving unit 901 is used forreceiving the downlink data transmitted by a base station via a downlinkcomponent carrier, the data processing unit 902 is used for decoding thereceived downlink data, and obtaining the response signals of thedownlink data according to the decoding result, the first resourceselecting unit 903 is used for selecting the uplink resources fortransmitting the response signals from available resources and selectingcorresponding modulation symbols if the component carrier fortransmitting the downlink data includes a secondary component carrier;wherein the available resources include resources corresponding to apreconfigured primary component carrier and the resources allocated tothe secondary component carrier by the base station, and the signaltransmitting unit 904 is used for transmitting the response signals byusing the selected uplink resources and the corresponding modulationsymbols.

In this embodiment, the states of the response signals are mapped byusing the uplink resources and the modulation symbols in the uplinkresources. In this way, the mobile station selects the uplinks resourcesand selects corresponding modulation symbols according to the states ofthe response signals. Thus, the mobile station may transmit themodulation symbols, and the base station may judge whether thetransmitted downlink data are correctly received after receiving themodulation symbols. This is similar to the prior art, which shall not bedescribed any further.

As shown in FIG. 9, the mobile station may further comprise aninformation receiving unit 905 for receiving the indices of theresources transmitted by the base station, the resources being allocatedto the downlink secondary component carrier by the base station.

As shown in FIG. 9, the mobile station further comprises a secondresource selecting unit 906 for selecting the uplink resources fortransmitting the response signals and corresponding modulation symbolsfrom the available resources if the component carrier for transmittingthe downlink data is a primary component carrier; wherein the availableresources include the resources corresponding to the preconfiguredprimary component carrier.

In the above embodiment, the first resource selecting unit 905 and thesecond resource selecting unit 906 are specifically used for selectingthe uplink resources for transmitting the response signals and themodulation symbols by using a preconfigured mapping relation between thestate of the response signals and the selected resources and themodulation symbols according to the state of the response signals;wherein a selected resource is one of the available resources.

And wherein in the mapping relation, the resource corresponding to theresponse signal that is N/D is not selected; N and D are notdifferentiated, where N represents data is received with error, and Drepresents no downlink control data is received; and when the responsesignals are all N/D, no resource is selected. Wherein, the availableresources shown in tables 3A, 4A and 5A may be selected according to thestate of the response signals.

Preferably, the uplink resources and the corresponding modulationsymbols are selected by using the mapping relations shown in tables 3B,4B and 5B as described above, which shall not be described any further.

Furthermore, the first resource selecting unit 905 is used to select theuplink resources for transmitting the response signals and themodulation symbols by using a preconfigured mapping relation between thestate of the response signals and the selected resources and themodulation symbols according to the state of the response signals.

Wherein in the mapping relation, the resource corresponding to theresponse signal that is N/D is not selected; and when the secondresponse signal belonging to the same component carrier is N, theresource corresponding to the response signal which is N is not used;

No matter how many CCs are configured for the mobile station, if thedownlink data are only transmitted in the PCC, the mapping needs to beperformed by using resource mapping scheme in LTE, i.e. the lowest CCEindex of the PDCCH in the PCC.

Wherein, for the response signals with 4 bits and configured with 2 CCs,the available resources shown in Table 6A may be used, and uplinkresource selection may performed preferably by using the mappingrelations shown in Table 6B; for the response signals with 4 bits andconfigured with 3 CCs, the available resources shown in Table 7A may beused, and uplink resource selection may performed preferably by usingthe mapping relations shown in Table 7B; and for the response signalswith 3 bits and configured with 2 CCs, the available resources shown inTable 8A may be used, and uplink resource selection may performedpreferably by using the mapping relations shown in Table 8B.

Furthermore, the mobile station may comprise a storage unit 907 forstoring the preconfigured resources, the allocated resources and theabove tables of mapping relation.

It can be seen from the above embodiment that when data are transmittedvia SCCs, a case of insufficient of resources occurs. As such, the basestation allocates extra resource based on the number of TBs used fortransmitting data, and transmits the indices of the resources to themobile station via a PDCCH, so that the mobile station may feed backresponse signals by using the preconfigured resources and the extraallocated resources, and may feed back the response signals at arelatively low cost which solves the problem of insufficient resourcesin the prior art.

FIG. 10 is a schematic diagram of the structure of the communicationsystem in accordance with the 6th embodiment of the present invention.As shown in FIG. 10, the communication system comprises a base station1001 and a mobile station 1002; wherein the base station 1001 may usethe base station as described in the 4th embodiment, and the mobilestation 1002 may use the mobile station as described in the 5thembodiment, which shall not be described any further.

It can be seen from the above embodiment that when data are transmittedby the base station via SCCs, a case of insufficient of resourcesoccurs. As such, the base station allocates extra resource based on thenumber of TBs used for transmitting data, and transmits the indices ofthe resources to the mobile station via a PDCCH, so that the mobilestation may feed back response signals by using the preconfiguredresources and the extra allocated resources, and may feed back theresponse signals at a relatively low cost which solves the problem ofinsufficient resources in the prior art.

An embodiment of the present invention further provides acomputer-readable program, wherein when the program is executed in abase station, the program enables a computer to carry out the method fortransmitting uplink response signals as described in the 1st or 2ndembodiment in the base station.

An embodiment of the present invention further provides a storage mediumstoring a computer-readable program, wherein the computer-readableprogram enables a computer to carry out the method for transmittinguplink response signals as described in the 1st or 2nd embodiment in abase station.

An embodiment of the present invention further provides acomputer-readable program, wherein when the program is executed in amobile station, the program makes a computer to carry out the method fortransmitting uplink response signals as described in the 3rd embodimentin the mobile station.

An embodiment of the present invention further provides a storage mediumstoring a computer-readable program, wherein the computer-readableprogram enables a computer to carry out the method for transmittinguplink response signals as described in the 3rd embodiment in a mobilestation.

The above devices and methods of the present invention may beimplemented by hardware, and may also be implemented by hardware incombination with software. The present invention relates to such acomputer-readable program that when the program is executed by a logiccomponent, it enables the logic component to implement the devices orconstitutional parts as described above, or enables the logic componentto implement the methods or steps as described above. The presentinvention relates also to a storage medium for storing the aboveprogram, such as a hard disk, a floppy disk, a CD, and flash memory,etc.

The present invention are described above in conjunction with theembodiments, however, it will be apparent to those skilled in the artthat such description is exemplary only and is not limitative to theprotection scope of the present invention. Various variations andmodifications may be made by those skilled in the art without departingfrom the spirits and principle of the present invention, which will fallwithin the protection scope of the present invention.

What is claimed is:
 1. A user equipment (UE), comprising: a receiverconfigured to receive downlink data transmitted by a base station via adownlink component carrier; a circuit configured to select uplinkresources from available resources for transmitting response signalsobtained by decoding the received downlink data and select correspondingmodulation symbols when the downlink component carrier for transmittingthe downlink data includes a secondary component carrier; wherein theavailable resources include resources corresponding to a primarycomponent carrier and resources allocated to the secondary componentcarrier by the base station; and a transmitter configured to transmitthe response signals by using the selected uplink resources and thecorresponding modulation symbols; wherein the circuit is furtherconfigured to select the uplink resources for transmitting the responsesignals and the modulation symbols by using a mapping relation between astate of the response signals and the selected resources and themodulation symbols according to the state of the response signals; and,wherein the mapping relation includes cases in which the resourcecorresponding to the response signal that is NACK/DTX is not selected;where NACK represents Negative Acknowledgement, and DTX representsDiscontinuous Transmission; and when the response signals are all DTX,no resource is selected.
 2. The UE according to claim 1, wherein thereceiver is further configured to receive indices of the resourcestransmitted by the base station, the resources being allocated by thebase station to the downlink secondary component carrier.
 3. The UEaccording to claim 1, wherein the circuit is further configured toselect the uplink resources for transmitting the response signals andcorresponding modulation symbols from the available resources when thecomponent carrier for transmitting the downlink data is a primarycomponent carrier; wherein the available resources include the resourcescorresponding to the primary component carrier.
 4. A base station,comprising: a transmitter configured to transmit data to a userequipment (UE) by using a downlink secondary component carrier; acircuit configured to allocate resources according to a number oftransmission blocks for transmitting downlink data in the secondarycomponent carrier, such that the UE is able to select the uplinkresources for transmitting response signals from available resources andselect corresponding modulation symbols, wherein, the availableresources include resources corresponding to a primary component carrierand the resources allocated to the secondary component carrier; whereinthe UE is further able to select the uplink resources for transmittingthe response signals and the modulation symbols by using a mappingrelation between a state of the response signals and the selectedresources and the modulation symbols according to the state of theresponse signals; and, wherein the mapping relation includes cases inwhich the resource corresponding to the response signal that is NACK/DTXis not selected; where NACK represents Negative Acknowledgement, and DTXrepresents Discontinuous Transmission; and when the response signals areall DTX, no resource is selected.
 5. The base station according to claim4, wherein the transmitter is further configured to transmit indices ofthe resources allocated by the circuit to the UE.
 6. The base stationaccording to claim 4, wherein the circuit is further configured toselect resources from a first resource table if the number of thetransmission blocks for transmitting downlink data is 1, each of theelements in the first resource table including 1 resource, and to selectresources from a second resource table if the number of the transmissionblocks for transmitting downlink data is 2, each of the elements in thesecond resource table including 2 resources.
 7. The base stationaccording to claim 5, wherein the transmitter is further configured totransmit the indices of the allocated resources to the UE via a physicaldownlink control channel (PDCCH) of the secondary component carrier forscheduling the downlink data.
 8. A user equipment (UE), comprising: acontrol circuit configured to select uplink resources from availableresources for transmitting response signals obtained by decodingdownlink data received from a base station via a downlink componentcarrier, and the control circuit configured to select correspondingmodulation symbols when the downlink component carrier for transmittingthe downlink data includes a secondary component carrier, the availableresources include resources corresponding to a primary component carrierand resources allocated to the secondary component carrier by the basestation; and a transmitter configured to transmit the response signalsby using the selected uplink resources and the corresponding modulationsymbols; wherein the control circuit is further configured to select theuplink resources for transmitting the response signals and themodulation symbols by using a mapping relation between a state of theresponse signals and the selected resources and the modulation symbolsaccording to the state of the response signals; and, wherein the mappingrelation includes cases in which the resource corresponding to theresponse signal that is NACK/DTX is not selected; where NACK representsNegative Acknowledgement, and DTX represents Discontinuous Transmission;and when the response signals are all DTX, no resource is selected. 9.The UE according to claim 8, further comprising a receiver configured toreceive indices of the resources transmitted by the base station, theresources being allocated by the base station to the downlink secondarycomponent carrier.
 10. The UE according to claim 8, wherein the controlcircuit is further configured to select the uplink resources fortransmitting the response signals and corresponding modulation symbolsfrom the available resources when the component carrier for transmittingthe downlink data is a primary component carrier; wherein the availableresources include the resources corresponding to the primary componentcarrier.
 11. A system comprising: a base station comprising atransmitter configured to transmit data by using a downlink secondarycomponent carrier; a circuit configured to allocate resources accordingto a number of transmission blocks for transmitting downlink data in thesecondary component carrier; and a user equipment (UE), comprising: acontrol circuit configured to select uplink resources from availableresources for transmitting response signals obtained by decoding datareceived from the base station via a downlink component carrier, and thecontrol circuit configured to select corresponding modulation symbolswhen the downlink component carrier for transmitting the data includes asecondary component carrier, the available resources include resourcescorresponding to a primary component carrier and resources allocated tothe secondary component carrier by the base station; and a transmitterconfigured to transmit the response signals by using the selected uplinkresources and the corresponding modulation symbols, wherein the controlcircuit is further configured to select the uplink resources fortransmitting the response signals and the modulation symbols by using amapping relation between a state of the response signals and theselected resources and the modulation symbols according to the state ofthe response signals, and, wherein the mapping relation includes casesin which the resource corresponding to the response signal that isNACK/DTX is not selected; where NACK represents NegativeAcknowledgement, and DTX represents Discontinuous Transmission; and whenthe response signals are all DTX, no resource is selected.